I purchased the Witcher 2 through Steam and have been playing with no problems up until Steam applied the latest patch. I have saves about 30 minutes after leaving Flotsom, but everytime I try to load one, it crashes to desktop. I can load any game saved prior to leaving Flotsom and play as long as I want, but as soon as I leave Flotsom, it crashes to desktop. Any ideas?

Corrupt install. Try again. If need be you might have to do a complete reinstallation.

Mind uploading the save file? I can try it out on my PC, and if it fails, that means the save is corrupt. If it works fine, that means your game installation is corrupted.

Just an idea.

Because you are crashing when starting chapter 2 that means the crash most likely is caused from trying to get the cut sceen to play. To me that means its a bad installation. or the patch caused the issue.

First try reinstalling the patch. If that fails you will be forced to reinstall the game.